President Obama traveled to crucial Iowa on Tuesday to make his case that Congress should extend middle-class tax cuts for a year — but not tax breaks for the wealthiest Americans, as Republicans also want to do.

The president is forcing an election-year showdown with Republicans, including his opponent Mitt Romney. And he is betting that he can win the argument by taking it on the road, out of Washington, and presenting it directly to Americans.

To make his case, Obama visited a middle-class family in Cedar Rapids whose taxes could go up by $2,000 if Congress doesn’t act.

But the quick campaign trip was also about Iowa, the state that propelled Obama to his party’s nomination when he won the caucuses here four years ago — and a state that is increasingly shaping up as one of the most challenging battlegrounds of the 2012 election.

“My opponent and his allies in Congress, they sincerely believe that prosperity comes from the top down,” Obama told a crowd of about 1,600 at Kirkland Community College in Cedar Rapids. “They believe that if we spend trillions of dollars more in tax cuts, mostly for the wealthy, that somehow it will create more jobs.

“And I think they’re wrong,” he added.

Obama wove the tax-cut argument into his broader campaign message, offering a choice between his own vision of strengthening the middle class by protecting the government programs that benefit them and that of Romney, whose plans to slash spending and cut taxes for top earners would come, Obama said, at the expense of the middle class.

Obama presented a similar contrast between Romney’s plans to roll back banking regulations and attempt to repeal the Affordable Care Act, as well as his past opposition to the auto industry bailout, to the president’s own policies to invest more in infrastructure and education, help homeowners refinance underwater mortgages and keep student loan rates low.

“All these things that make up a middle-class life, they’re all tied together,” Obama said. “They’re all central to the ideas that made this big, diverse, hopeful, optimistic, hardworking country great. The idea that if you work hard, you can have the security to make of your life what you will. The idea that we are all in this together. We are all individuals, and we have to take responsibility, but ultimately there are some things we do together.”

Romney, campaigning in Colorado, denounced Obama’s plan to let tax breaks expire for higher-income earners, saying it would raise taxes on what he called “job creators and small businesses.”

Obama’s trip to Iowa, billed a campaign trip by the White House, came the day after the president announced his proposal to extend George W. Bush-era tax cuts for the middle class at an official White House event staged in the East Room with working families. Obama announced that he would support a one-year extension for households earning less than $250,000, which he said would cover roughly 98 percent of households.

White House press secretary Jay Carney, speaking to reporters aboard Air Force One en route to Iowa on Tuesday, was asked whether the proposal is official policy or a campaign issue. “Both,” he said.

“When the president proposes something and brings it to the American people, Republican opposition often wanes,” Carney said. Other examples, he said, include the payroll tax cut and his proposal, which is now law, to extend low interest rates for college loans.

“We believe that if the president makes his case to Americans around the country, then the Republican position will become increasingly untenable and we can accomplish something for the American people, now, before the election,” Carney said.

In addition to visiting Iowa, Obama’s reelection campaign blanketed 15 states, most of them battlegrounds, with details on how residents of each state would benefit from an extension of the tax cuts — and how many could be harmed by Romney’s tax plan.

Obama also visited the McLaughlin family in Cedar Rapids to illustrate the value of his tax proposal on a typical family. Jason McLaughlin is a high school principal; his wife, Ali, is an account manager for a document-scanning business. They have a 4-year-old son, Cooper, and another on the way. (Obama asked them what they’re naming him, but they haven’t decided yet. “I asked them what about Barack,” the president said afterward, during his speech. “That was not yet on the list.”)

The McLaughlins together earned $82,000 in 2011. They have received about $4,900 in tax relief over Obama’s first term, from the Making Work Pay tax credit that was part of the Recovery Act, as well as from the payroll tax cuts of 2011 and 2012.

If the Bush-era tax cuts expire, the McLaughlins could face a tax increase of about $2,000, according to the Obama campaign.

Obama sat with the McLaughlins at their kitchen table, in a modest, chocolate-brown one-story home near the corner of Robinhood Lane and Prairie Road. They chatted about the McLaughlins’ finances, about Jason McLaughlin’s new job as a principal and his experience coaching girls track.

Obama talked about coaching his daughter Sasha’s basketball team, and how the team has moved behind the “bumblebee” strategy of swarming the ball. “Now, they run plays,” he said.