Pennsylvania is a battleground state once again.

From the Pittsburgh Tribune-Review:

Keep those eyes on bellwethers Ohio and Pennsylvania 

Perception and reality are two different things in politics.

On paper, Republicans Pat Toomey of Pennsylvania and Rob Portman of Ohio should be losing in the polls in their U.S. Senate re-election races. 

Both men have been hammered for a month over whether they will support their party's presumptive nominee, their opposition to voting on President Obama's Supreme Court nominee and their refusal to enact new gun legislation after the massacre in Orlando. 

Yet both are defying conventional political wisdom. 

Toomey increased his lead over Democrat Katie McGinty by 8 percentage points in the latest Quinnipiac survey. 

Portman's numbers improved by 9 points, placing him in a tie with Democrat Ted Strickland, a former governor who lost his re-election bid to John Kasich in 2010. 

The two Republicans are competing in critical states that offer insight into whether Democrats can regain House and Senate majorities in November. 

In short, if you want to know who will hold or retake the Senate majority, watch Toomey's battle with McGinty and Portman's with Strickland. 

As for control of the House, watch what's happening with congressional races in these two Rust Belt states. 

Ohio and Pennsylvania are microcosms of the Democrats' national difficulties in trying to win the House, said Kyle Kondik, author of “The Bellwether: Why Ohio Picks the President” and manager of the University of Virginia's Crystal Ball, the respected online political website. 

“Democrats have a path to the House majority but the Republican advantage in Ohio and Pennsylvania helps illustrate their challenges,” Kondik said. 

Republicans control 12 of 16 House seats in Ohio and 13 of 18 in Pennsylvania — overwhelming majorities in two states that Obama won twice and that, at the moment, Democrat Hillary Clinton is favored to win in November, despite close polling against Republican Donald Trump. 

In Ohio, Democrats don't really have credible targets, according to Kondik. Rep. David Joyce in Ohio's 14th Congressional District is vulnerable “on paper, but after Joyce won his primary, there's not much buzz about that race.” 

In Pennsylvania, Democrats hope to win Bucks County's open 8th District seat, which is the kind of competitive suburban seat they need to win back the House. “Realistically, they don't have much of a chance for any additional gains,” Kondik said. 

Before 2010, Democrats held a healthy majority of House seats in both states but lost five in each state to that year's GOP wave. 

Voters were dissatisfied with government overreach; the moderate Democrats who easily won those seats in 2006 — such as Patrick Murphy in Bucks and Jason Altmire in Western Pennsylvania — lost when their leadership forced them into votes that went against their districts' more traditional, more moderate values. 

There has been much speculation over the impact Trump will have on Republicans' congressional majorities, and much speculation that his awful months of May and June would show him sliding in both states' polls. 

Surprisingly, he didn't slide. In fact, in the same Quinnipiac survey showing Toomey and Portman gaining traction, Trump held steady.

“If Trump wins Ohio and Pennsylvania, Portman and Toomey should also win,” Kondik predicts. “But if Trump loses both states — and especially if he loses them badly (by more than five points) — both incumbents are in trouble.” 

Kondik's Crystal Ball has shifted Pennsylvania's rating in the presidential contest a bit toward Trump. That moves 2016's potentially most important state from “Likely Democratic” to “Leans Democratic,” despite the organizational and 2-to-1 voter-registration advantages Clinton holds in the state. 

Despite the political theatre of House Democrats staging their “sit-in” last week, Americans have grown weary of Washington spectacles and blame-shifting. So instead of appearing to care about gun legislation, Democrats came across as caring all about themselves, knowing nothing would come of their stunt and trying to benefit from it by fundraising off it. 

History shows that you cannot produce a wave election; such events evolve from the bottom up. 

Although anything could happen between now and November, the best way to see which party appears likely to win House and Senate majorities is to keep your eyes on Pennsylvania and Ohio — and to keep your eyes off the contrived spectacles. 

Salena Zito covers politics for the Tribune-Review (szito@tribweb.com).