Former Sen. Dan Coats (R-Ind.) said Wednesday that he is “answering the call” to challenge Sen. Evan Bayh (D) and has hundreds of volunteers working to collect the thousands of signatures that he needs by next week’s deadline.

“We’re off and running,” Coats said on the Indiana radio station WOWO in Fort Wayne, his political base. “We know it’s an uphill climb, but I know this state — I know these people. I believe that they don’t want what’s going on in Washington, and it’s been supported by our current Senator.”

Coats, whom Bayh succeeded in the Senate after he retired 11 years ago, said numerous supporters are “out all over the state” helping him secure the signatures of at least 4,500 registered voters, including at least 500 in each of Indiana’s nine Congressional districts, by the Feb. 19 deadline to qualify for the May 4 primary ballot.

Coats’ campaign likely will collect at least twice as many to ensure that it easily meets the minimum threshold.

“We’ve got to dot some i’s and cross some t’s on the process of getting certified and so forth. We’re off to a great start in doing that,” Coats said. “We’re in a time crunch to do it because the deadline is coming up. But hundreds of volunteers and Hoosiers are helping us, and we’re going to do it.”

Coats said his campaign that would respond comprehensively to incessant Democratic attacks on his background as a registered lobbyist. He said that his work has been mostly “consultation and strategy,” not lobbying, and that the two firms that he has been affiliated with register all of their principals as lobbyists out of an abundance of caution.

“It’s not anywhere near what they’ve said I’ve done, and people will then have to look at that and make a decision,” he said.