After more than a month back home focused mostly on electoral politics, Congress reconvenes next week with hopes of quickly averting a government shutdown and reauthorizing a few other federal programs before rushing home to get back on the campaign trail.

But two issues out of lawmakers' control -- whether President Obama plans to make any moves on immigration, or seeks congressional authorization to confront the hard-line Islamist groups dominating parts of northern Iraq and Syria -- could upend what House and Senate leaders have been hoping would be a relatively drama-free month.

And there's been concern that the lack of agreement on virtually anything in recent months might lead to another shutdown -- especially with fewer than 15 days of legislative work scheduled this month.

"September is going to be brief, but busy," Speaker John A. Boehner (R-Ohio) warned House Republicans on a conference call Wednesday afternoon, according to an official who listened in on the call. Boehner said that the House Republican "closing argument" to voters in the coming weeks would focus on economic issues, including reminders of the dozens of measures passed in the last two years -- mostly ignored by the Democratic-controlled Senate -- that would help spur job creation.

It was the second time this month that Boehner has spoken with his caucus. Aides said both calls signaled that GOP lawmakers remain remarkably unified going into the final stretch of the campaign season -- and that the lack of tension stems mostly from Boehner's decision to hold votes on two separate border security measures just before the recess began.

That move allowed Republicans to go home and tell voters that they had done what they could to address the historic influx of children illegally crossing the U.S.-Mexico border. In the weeks since, concerns about massive waves of young migrants have subsided as the number of illegal crossings has dropped dramatically.

Obama is weighing whether to use executive authority to overhaul his administration's immigration and deportation policies, possibly by deferring the deportations of millions of illegal immigrants whose children have already been granted temporary status. But the White House has signaled in recent days that it might delay any significant policy announcements on immigration until after the elections, in part to avoid upending the chances of several Democratic senators fighting competitive reelection battles.

Whether Obama seeks authorization to strike the Islamic State, currently occupying parts of Iraq and Syria, also remains unclear. Members of both parties -- including, in recent days, several Democratic senators -- are calling on the president to quickly unveil plans to escalate military attacks on the group beyond the limited airstrikes and diplomatic attempts to form a coalition against the militants. Obama warned Wednesday that attempts to address the threat from the group could extend into the next year.

Absent any announcement of changes in immigration policy or a sudden request for military authorization, aides to House and Senate leaders said this week that the process of averting another government shutdown should move quickly and easily. Top leaders in both parties are eager to avoid the political drama and fallout from last year's shutdown -- especially just a few weeks before Election Day.

House Republicans are expected to unveil a short-term spending plan next week that would continue current spending levels through at least early December, according to top aides. What remains uncertain is whether Boehner and his leadership team will add other items to the measure, including reauthorization of the Export-Import Bank, the federal entity that provides loan guarantees to foreign purchasers of American goods, including airplanes. Reauthorizing the bank has emerged as a cause celebre for conservative Republicans, who believe that the bank is an example of "crony capitalism," or Washington's practice of putting corporate interests over ordinary people.

In order to reauthorize the bank, Boehner will need to strike an agreement with Rep. Jeb Hensarling (R-Tex.), who chairs the House Financial Services Committee that oversees the bank, and who has emerged as one of its fiercest critics. Aides said Wednesday that no deal has been reached, but that an agreement to authorize a short-term extension -- possibly only until early next year -- is in the works. No final decision on how to proceed is expected to be made until the middle of next week, after lawmakers return to Washington and confer on how to proceed.

With the House tasked with starting the process of passing a short-term spending plan and reauthorizing the Export-Import Bank, the Senate is poised to begin September holding votes on measures designed to shore up support among minorities, women and working-class voters -- key Democratic-leaning constituencies in several close races.

Democrats are expected to hold a vote as early as Monday night on a measure that would give Congress the power to overturn controversial Supreme Court campaign finance decisions. The measure, which is ultimately expected to fail due to a lack of Republican support, is viewed as a political gesture to appease liberals and Democratic base voters who've bemoaned the flood of unregulated money into campaigns since the 2010 Citizens United Supreme Court decision.

The issue of unlimited campaign donations is a special concern of Senate Majority Leader Harry M. Reid (D-Nev.), who has spent much of the past year blasting the wealthy industrialist brothers Charles and David Koch for financing outside political groups pouring millions of dollars into several states in hopes of unseating Democratic senators.

During his conference call Wednesday, Boehner faulted Reid for planning to hold the vote: "At a time when Americans are concerned about the economy, jobs and the security of our country, the leader of the dysfunctional, do-nothing Senate plans to spend the final legislative days before November talking about the Koch brothers," he said.

If Democrats fail to advance the campaign finance measure, they will likely try holding votes on a proposal to raise the federal minimum wage, and another to override the Supreme Court decision in the Hobby Lobby case and require all employers to abide by the contraception mandate included in the Affordable Care Act, even if those employers claim to have religious objections. These measures also lack sufficient GOP support to advance and would be ignored by the GOP-controlled House.

On paper, the September congressional calendar suggests that both chambers want to work quickly on its official duties. House and Senate votes will be held Monday evening and both chambers plan to meet through the end of the week. The House is scheduled to break on Sept. 19 for a week in observance of Rosh Hashanah, which is Sept. 24. If needed, the House will reconvene on Sept. 29 and leave town for the remainder of the election season on Oct. 2.

In the Senate, Reid plans to keep working through Sept. 23, then break for the Jewish holiday and not return until after Election Day.

Still, if recent congressional history is any guide, plans will change and last-minute votes will be held. The campaign trail might have to wait a few extra days.