Opinion polls put the Tory and Labour percentage of the vote within the margin of error, with the notional lead swapping: https://en.wikipedia.org/wiki/Opinion_polling_for_the_next_United_Kingdom_general_election#2018

The bookmakers think the Tories are slightly more likely to get the most seats - odds of 19/20, compared to 11/10 for Labour: https://www.oddschecker.com/politics/british-politics

Though those odds are quite confusing - Corbyn is only 4/1 to be the next PM, but the odds for May to be out by April 2019 are over 50%. This indicates they think there's a good chance May will resign the party leadership, and hand over to another Tory (though nobody has a good idea who).

With the odds for 'most seats' so close, another hung parliament would look like the most likely result of a general election. How that'd work out, who knows - the DUP would again offer a Tory leader support, but explcitly for a hard Brexit now - which might still alienate enough Tories to sink it. But if Corbyn needed SNP support, they might hesitate, unless they see a way of fixing Brexit and taking credit.