FRIDAY’S CAMPAIGN ROUND-UP…. Today’s installment of campaign-related news items that wouldn’t generate a post of their own, but may be of interest to political observers.

* To the relief of the DSCC, former Wisconsin Gov. Tommy Thompson (R) announced yesterday that he will not run for the Senate this year. The decision improves Sen. Russ Feingold’s (D) re-election chances considerably.

* After Charlie Crist (R) vetoed an education bill championed by conservative Republicans in the state legislature, former Sen. Connie Mack (R) resigned as chairman of Crist’s Senate campaign.

* As speculation about Crist’s future in the GOP intensifies, NRSC Chairman John Cornyn (R-Texas) is warning the Floridian not to run as an independent.

* The latest Mason-Dixon poll in Nevada shows Senate Majority Leader Harry Reid (D) trailing Sue Lowden (R) by 10 points, even when a full slate of third-party candidates is included in the mix.

* In Hawaii’s upcoming special election, a new Research 2000 poll shows Charles Djou (R) narrowly leading a three-way contest. He’s running against two Democrats at the same time, splitting the party’s support in half.

* The DNC is prepared to invest more than $50 million in cash and services for House, Senate, and gubernatorial campaigns this year, starting in June.

* The latest Research 2000 poll in Arkansas shows Sen. Blanche Lincoln (D) with a 12-point lead over her primary challenger, Bill Halter, 45% to 33%.

* Michael Heath kicked off his independent gubernatorial campaign in Maine earlier this week. Yesterday, he quit.

* And most likely presidential candidates create political action committees to support like-minded candidates, raising money specifically for the purpose of donating it. Former half-term governor Sarah Palin’s PAC spent $409,000 in the first quarter, but only $9,500 in support of candidates.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.