Sen. Joe Lieberman (I-Conn.) has his first Democratic challenger — former state Secretary Susan Bysiewicz.

The Democrat got an early jump on 2012 Tuesday, announcing her campaign for the seat after enduring a disastrous 2010 cycle.  

"We need a Senator who is 100% focused on helping our state, and Senator Joe Lieberman has been focused on everything but Connecticut," Bysiewicz said in an e-mail announcing her 2012 plans, according to the Connecticut Mirror

The announcement from Bysiewicz places some pressure on other Democrats who have expressed interest in the contest, particularly Connecticut Reps. Joe Courtney and Chris Murphy.

Still, Bysiewicz will have plenty to prove in a Democratic primary, and her entrance into the race certainly won't clear the field. Some Democrats have expressed worry that two failed campaigns in 2010 could hamper Bysiewicz in 2012. 

After mulling a run for governor in 2010, Bysiewicz abruptly decided to run for attorney general instead. That race resulted in disaster after a court ruled that she didn't meet the state's criteria for serving as attorney general, which ended her campaign.

As the Mirror details, management questions also arose toward the end of her tenure as secretary of state. 

Lieberman has not yet announced his 2012 plans, which has some political observers in the state thinking he will opt to not seek another term in 2012. The independent senator would have to again create a party line for his candidacy to get his name back on the ballot next year. 

While unlikely, it's also possible that Lieberman could run under the banner of one of the major parties in 2012. Lieberman told The Ballot Box in December that he has received plenty of encouragement from Democratic colleagues and that he expects to make a final decision on 2012 early this year.