Attorney Roxanne Conlin (D) is saying that she is “more likely than not— going to challenge Sen. Chuck Grassley (R-Iowa) in 2010.

Conlin, the losing Democratic nominee for governor in 1982 and a former president of the trial lawyers’ national association, on Thursday told the Des Moines Register, “I don’t know how this is going to come together, but I have reached the point where I would like to do it.—

Democratic leaders are promising a vigorous challenger for Grassley, who has won all four of his Senate re-election bids with at least 66 percent of the vote against weak opposition. The party’s field currently includes a pair of little-known former state legislators, Tom Fiegen and Bob Krause, who have raised very little money.

One potential candidate is Christie Vilsack, a lawyer whose husband, Tom Vilsack, is a former Iowa governor and President Barack Obama’s Agriculture secretary.

A Research 2000/Daily Kos survey conducted Oct. 12-14 gave Grassley a 51 percent to 39 percent advantage over Vilsack and a 51 percent to 40 percent lead over Conlin.

Grassley reported raising $865,000 in this year’s third quarter and had $4.4 million left in his campaign account at the beginning of October.