Sen. Mark Pryor, D-Ark., doesn’t have an opponent yet, but he’s being forced to play defense anyway.

Hit from both sides on the air this week, Pryor launched the first television ad of his re-election campaign on Friday. The ad, coming about 17 months before the general election, is backed by a “significant statewide buy,” according to a Democratic spokesman.

https://www.youtube.com/watch?v=m5JDuTkHt20

New York Mayor Michael Bloomberg’s super PAC, Mayors Against Illegal Guns, launched an ad campaign on May 24 hitting Pryor for not supporting expanded background checks — a bill the vast majority of Senate Democrats supported.

Meanwhile, Senate Conservatives Action went on the air this week to highlight Pryor’s propensity to vote most of the time with President Barack Obama.

Pryor gets out the most important piece of information in his ad in the first seven seconds: “The mayor of New York City is running ads against me because I opposed President Obama’s gun control legislation.”

The line is meant to highlight that Pryor’s values are in line with Arkansas, not New York or Washington, D.C. That’s a vital message he needs to get across in a state trending decidedly away from Democrats.

(See also in Roll Call: Pryor Can’t Escape 2010 Comparison)

Rothenberg Political Report/Roll Call rates this race as Pure Tossup.