From Eric Dondero:

Rand Paul is a diehard Ron Paulist on economics and Constitutional matters down-the-line. But his image and emphasis on the issues may be more closely matched with newly elected Massachusetts Senator.

From The Louisville Courier-Journal:

Republican prospects in every state, particularly in federal elections, improved still more a couple of days after the Massachusetts vote.

Paul's father is U.S. Rep. Ron Paul of Texas, whose 2008 presidential campaign base provides the financing to make his son competitive. But Rand Paul is not just running on that base or his father's name.

He is riding much the same wave that elected Scott Brown: Voters who don't believe the economic stimulus package was worth the $1trillion it added to the national debt, who fear health reform, and who want the federal government reined in, starting with its spending habits.

Notably, the younger Paul has broken with the elder on foreign policy issues. For instance, Rand Paul takes a Scott Brown position opposing the closure of Gitmo and relocation of Gitmo detainees to the United States.

As the article out of Kentucky suggests, he seems to be "catching the Scott Brown wave."