The Chamber of Commerce has launched two new ads focusing on what are expected to be some of the closest Senate races of the 2016 cycle: the seats up in Pennsylvania and Ohio.

In Pennsylvania, the business lobby group's political advocacy arm has launched a 30-second ad lauding Republican senator Pat Toomey. The spot celebrates Toomey as a "practical and constructive conservative" who puts "partisanship aside to do what's right for Pennsylvania." Watch the video below:

The ad notes Toomey's support for the Keystone XL pipeline and heavily emphasizes his work reaching "across the aisle."

Toomey, a former congressman and one-time president of the conservative Club for Growth, was first elected to the Senate in 2010 in a hard-fought race against Democrat Joe Sestak. Toomey had won the GOP nomination after challenging sitting Republican senator Arlen Specter, who switched parties just days after Toomey announced his candidacy. Specter went on to lose the Democratic nomination to Sestak.

2010 was a good year nationally for Republicans, but with the presidential race at the top of the ticket, Democrats hope to take back Pennsylvania. Sestak is among the Democrats who are running to take on Toomey, and early polls show Toomey leading him at varying margins. Sestak was also seen over the holiday weekend running into at least two small children.

Next-door in purple-state Ohio, incumbent Republican Rob Portman is also in a difficult race for reelection. Former governor Ted Strickland, the likely Democratic candidate, is the subject of the Chamber's new ad there. The 30-second ad highlights bad economic statistics from Strickland's four years as governor and asks voters to "say no" to Strickland for the Senate. Watch the video below:

Both Portman and Strickland were on the ballot in Ohio in 2010. While Portman successfully won to succeed retiring Republican George Voinovich, Strickland lost his reelection bid as governor to Republican John Kasich. As the Chamber ad notes, Strickland moved to Washington soon after his defeat to run the advocacy arm of the Center for American Progress, a liberal think tank.

Early polls show a divided electorate in Ohio, with the latest Quinnipiac poll giving Strickland the advantage over Portman. But as in Pennsylvania, the Senate race in Ohio may have a lot to do with the state of the presidential race in that state.