If the 2012 election cycle has felt like a roller coaster ride for anyone, it's former Wisconsin governor Tommy Thompson (R). Since declaring his Senate candidacy, Thompson has been a top target of conservative groups, a Senate frontrunner, and now, an apparent underdog.

Does Thompson have another surge in him? His supporters aren't panicking yet, because it's very possible he does.

(Andy Manis/AP)

When Thompson won a brutal four-way primary in August, it was hardly in a dominating fashion. But national Republican strategists got the candidate they wanted: A four-term governor with nearly universal name ID and a moderate record.

Polling conducted just after Thompson's primary win showed why the GOP had something to celebrate. He led opponent Rep. Tammy Baldwin (D) by six points and nine points in two live-caller surveys.

Fast forward to this week, and things don't look so great for Thompson anymore. Suddenly, Thompson finds himself tied and losing by nine points in the two polls that previously showed him leading.

And his trajectory has resonated beyond Wisconsin. With just days left for Rep. Todd Akin (R) to remove himself from the ballot in Missouri (something that is looking like an unlikely proposition), Republican prospects there are looking dimmer. If Akin remains on the ballot, it will greatly reduce the GOP odds of picking up a seat that once looked very promising. That would make a Wisconsin pickup all the more crucial for the GOP.

Back in Wisconsin, Democrats have been consistently hitting Thompson over his work on the lobbying circuit after he left office. Both Baldwin's campaign and the Democratic Senatorial Campaign Committee have been pressing the argument, which party strategists believe has helped propel Baldwin into the lead.

“Four polls released this week show that we are moving in the right direction as the choice for Wisconsin voters has been made clear," Baldwin spokesman John Kraus said in a statement.

Bruised by an expensive primary campaign, Thompson's campaign coffers were badly depleted by the end. As he put it, his campaign was "broke." So he attempted to regroup, placing a renewed focus on fundraising, something which has been a weak point for him this cycle. He was off the airwaves for weeks, leaving a vacuum that Baldwin smartly filled with a message that dinged the Republican's image.

Republican strategists acknowledge the race has tightened, but maintain it is still within Thompson's reach. They remain encouraged for several reasons.

Thompson has signed on Keith Gilkes, a former campaign manager and chief of staff to  Gov. Scott Walker (R), the Republican standard-bearer in the state during the last two years. Thompson also got a hand Thursday from the Chamber of Commerce, which launched a new ad hitting Baldwin over her support for President Obama's health care law. And Thompson is back on the air with an ad echoing the health care attack against Baldwin.

"[Thompson] is the most successful politician in Wisconsin history," said Bill McCoshen, a former chief of staff to the Republican nominee and state secretary of commerce during his tenure as governor. "He got out of the gate slow because of a brutal primary where he was outspent 6-1. He has the resources he needs to draw a clear contrast with Tammy Baldwin."

Republicans hope to cast Baldwin as too liberal for the state and are hoping that competition at the top of the ticket could help Thompson. Polls (save for a Marquette Law School poll released Wednesday showing Obama leading Mitt Romney by 14 points) have shown a competitive presidential race in the Badger State, which the Republican nominee has not carried since 1984.

If Obama runs ahead of Romney by more than a few points in Wisconsin, that's certainly good news for Baldwin. Thompson can win some crossover voters, but ultimately, the better the president does, the better it is for the congresswoman.

Baldwin, who faced no primary challenge, put herself a strong position to compete in the fall, raising heaps of cash working to build enthusiasm among Democrats. She has indisputably seized the high ground in recent weeks and continued on offense Thursday with a new ad casting Thompson as unfriendly to middle class voters.

As the race approaches its final stretch, Democrats' messaging will really be put to the test. If their argument that Thompson is beholden to Washington is enough to cancel out positive feelings voters have from his tenure as governor, they could win. If Thompson's legacy in the state is what matters more, then Republicans could well walk away with a victory.