Former state Sen. Staci Appel filed federal paperwork this weekend to challenge longtime Rep. Tom Latham, R-Iowa, in the competitive 3rd District.

Appel, a Democrat, has been considering a run for several months against Latham, one of Speaker John A. Boehner’s top allies on Capitol Hill. In April, she told the Des Moines Register she had decided against a run, even though Democrats heavily recruited her for the race.

But Appel reversed course in the following months. Last week, she started hiring a team for a congressional bid, according to Iowa Democratic sources. Appel declined to comment last week, but she filed her candidacy paperwork with the Federal Election Commission on July 3. She did not immediately return a request for comment this morning.

Democrats argue this district should be competitive. It is one of the few districts that President Barack Obama won in 2012 that is represented by a House Republican. Obama received 51 percent in the district to GOP nominee Mitt Romney’s 47 percent.

But Latham far outperformed Romney in the district, defeating longtime Rep. Leonard Boswell, a Democrat, by 9 points. The two members faced off following the decennial redistricting process, which nixed a House district from the Hawkeye State.

Rothenberg Political Report/Roll Call rates this a Republican Favored contest.