Now that Missouri’s new Congressional lines have been finalized, Rep. Russ Carnahan (D) has a big decision to make about his political future.

Should he run in the new Republican-leaning 2nd district? Or should he challenge fellow Democratic Rep. William Lacy Clay in the new 1st district, where Carnahan resides? Or should he abandon Congress and run statewide?

The decision is not a simple one, even for a veteran politician and political legacy such as Carnahan.

“I’m exploring all options including, certainly, evaluating the map as passed,” he told Roll Call on Thursday. ”We’ll be laying that out going forward.”

Asked about a bid for lieutenant governor, a position his late father once held, he said, “I’m not going to comment on running for stuff. We’re evaluating what we have in front of us right now.”

Though the Carnahan name is well-known in Missouri and the 2nd district will contain about a third of his former constituents, Carnahan would face very significant challenges if he decides to run in a district made up of suburban and exurban areas outside of St. Louis.

Under the new district lines, President Barack Obama would have won 47.6 percent of the 2nd district vote in 2008. Missouri does not require voters to register as Democrats or Republicans, so no official data on voter affiliation for the district exists.

“It’ll be competitive in six years maybe,” a longtime Missouri-based Republican consultant said. “But right now it is really Republican and he would be a dream to run against because he’s got a record.”

But national Democrats seem to be steering Carnahan in that direction, which would avoid a racially divisive primary between two Democratic Members in the 1st district.

The Democratic Congressional Campaign Committee strongly endorsed the idea of a Carnahan run in the second district. “We are invested in ensuring Russ Carnahan represents Missouri families in the 2nd district in Congress,” DCCC Midwest Regional Press Secretary Haley Morris said in a statement.

Republicans, meanwhile, are lining up to run in the 2nd district, which is held by Rep. Todd Akin (R), who is widely expected to vacate it to run for Senate. Further proof of that came Monday as attorney Ed Martin abandoned his Senate bid in favor of a Congressional run.

Carnahan was the only name Martin mentioned in his announcement.

“Elected officials like Russ Carnahan have been focused on growing their power and enriching themselves instead of remembering our families,” Martin said in a statement posted to his website.

Former Ambassador Ann Wagner (R) is exploring a run for the 2nd district and state Sen. Jane Cunningham is another potential GOP candidate.

If Wagner and Cunningham run, the Republican field will likely be close to set.

“I think we might be at the field here because there’s just not a lot of room,” said the Republican consultant based in Missouri. “Martin is Evangelical and he’s a tea party type. And Wagner’s got the business community and Jane Cunningham would be the state Senator, the grass-roots type,” he said.

Carnahan is not expected to have much competition for the Democratic nomination if he does seek it in the 2nd district, where he would have to run well ahead of Obama next year in order to win.

The opposite would be true if he opts to run against Clay, a former chairman of the Congressional Black Caucus, in the heavily Democratic 1st district. But he would find big challenges there, too.

The new 1st district’s population is 49.5 percent black and 3 percent Hispanic. More than 60 percent of likely Democratic primary voters in the district would be black, according to a demographic breakdown provided by a Democratic source. And based on his previous elections over the past decade, the source said, Clay usually gets about nine out of every 10 African-American votes and a bit less than
70 percent of the white vote.

But Democrats in Missouri say the chance of a Member-vs.-Member primary remains.

“When you’ve got two seated Members of Congress living in the same district, there’s the potential that there will be a primary,” said Brian Wahby, chairman of the St. Louis Democrats.

“Democrats would obviously prefer not to have an intraparty fight, but if that happens, hopefully we can make sure everybody keeps it civil,” Wahby said.

For his part, Clay was definitive: “I will run, and I will win decisively.”

Roy Temple, a longtime Democratic strategist in Missouri, said Carnahan is “a reasonably pragmatic guy so I think he will [run] where he thinks he’s got some balance between his best ability to contribute and a reasonable likelihood of success.”

Shira Toeplitz contributed to this report.