6 a.m. on a Sunday is not what I consider an optimal time for a run.

Even so, this past Sunday, I found myself turning into a parking lot at Memorial Park at 5:50 a.m. to go for a run hosted by Beto O'Rourke, the Democrat congressman running for Senate against Ted Cruz.

This event was billed as a "running town hall," where you could jog alongside O'Rourke and ask him questions.

When I pulled in and got out of the car, he was already there, looking wide awake, chatting with people as they arrived, with topics ranging from the climate change forum he'd recently attended to the fact that military veterans possess a wide range of invaluable skills.

Even at this early hour, it was clear that O'Rourke is a talented politician, someone with a gift for highlighting the issues while also offering positive solutions.

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This run was the kickoff of a 24-hour marathon session, streamed live on Facebook, with town halls in Sugar Land and Houston, a "Bands With Beto" fundraising event, a midnight rally in Austin and an all-nighter at UT Austin, ending at 5:15 the next morning, with O'Rourke hopping on a plane back to Washington, D.C.

In short, an exhausting schedule, packed with everything except for sleep.

Runners are a stubborn group of people with a high tolerance for self-inflicted pain. I count myself as one of them. Over the years, I've lost count of all the toenails I've lost, the aches and pains I've developed and the number of times I've questioned my life choices, especially toward the end of a long run.

Running for political office, especially as a Democrat in Texas, it seems, is no different, requiring a similar level of stubbornness and tolerance for self-inflicted pain.

As we ran alongside O'Rourke, eventually stopping for a brief town hall forum outside the tennis courts, I found myself wondering: Can a Democrat win a state-wide office in Texas? Is that even possible?

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Then I remembered the lessons I've learned as a runner. When I first started running, I was an out-of-shape student, in a rural high school with a brand-new cross-country team. The coach was desperate for someone, anyone, to join, no matter how slow.

So I joined the team, and spent a full season struggling to run a full three miles, struggling to finish my races, struggling just to keep moving, to keep running, to keep doing something that felt impossible. I never became fast, but I stuck with running, and it grew on me to the point that I began looking forward to my runs.

Somewhere along the way, I learned that sometimes what seems impossible, is, in fact, entirely achievable, as long as you keep pushing the boundaries.

During a long run, there always comes a time when my mind tries to tell me, Stop. Enough. You can't do this.

However, once I learned to push past the self-doubt, the discomfort, the constant mental questioning, Is this even possible?, surprising things happened. I got faster. I ran longer distances. I redefined what possible meant for me.

Looking at O'Rourke, and the other runners who showed up at 6 a.m. on a Sunday, I find myself wondering if the time has come to redefine what possible means in Texas.

Rachel Fairbank is a science writer living in Houston.

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